20661588087 has 12 divisors (see below), whose sum is σ = 32046545016. Its totient is φ = 11806621680.

The previous prime is 20661588053. The next prime is 20661588109. The reversal of 20661588087 is 78088516602.

It is not a de Polignac number, because 20661588087 - 2⁸ = 20661587831 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20661578087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 70277364 + ... + 70277657.

It is an arithmetic number, because the mean of its divisors is an integer number (2670545418).

Almost surely, 2^20661588087 is an apocalyptic number.

20661588087 is a deficient number, since it is larger than the sum of its proper divisors (11384956929).

20661588087 is a wasteful number, since it uses less digits than its factorization.

20661588087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140555038 (or 140555031 counting only the distinct ones).

The product of its (nonzero) digits is 1290240, while the sum is 51.

The spelling of 20661588087 in words is "twenty billion, six hundred sixty-one million, five hundred eighty-eight thousand, eighty-seven".